There have already been 34 reports of wild pig sightings or nuisances in the district between January and May, compared to 56 reports in the whole of last year, and 31 in 2016, according to the latest figures from the Agriculture, Fisheries and Conservation Department.

The attack on two research assistants, a 39-year-old man 39 and a 41-year-old woman, was the first by one of the animals, and occurred near the university’s Lyttelton Road exit at the corner of Babington Path. The pair were taken to Queen Mary Hospital, in Pok Fu Lam, after the attack.

While the man was discharged late last week, the woman remains in hospital.

Excluding that incident, there have been seven incidents of people being injured by wild pigs in Hong Kong in the past five years, and department figures show the number of reported sightings has been climbing steadily in that time.

In 2013 the department received 294 complaints about wild pigs across the city. Two years later that number jumped to 518, with 738 reports last year.

On Hong Kong Island alone, the number of complaints rose from 98 in 2013, to 223 in 2015, and 324 in 2017 – an average of almost one a day.

Chan, who is also the chairman of the University of Hong Kong Staff Association, said the Mid-Levels West area had developed a bit of a wild pig problem, blaming the department for having been too “kind” to the wild hog.

“We can’t take the attack case too lightly this time,” he said. “Two people were injured, rather seriously.

“In the past, boar sightings were usually reported in the woods of Lung Fu Shan Country Park at the backyard of the university, and along Po Shan Road. Now they were encroaching the university campus. If they go further downhill, they will reach downtown Sai Ying Pun or Shek Tong Tsui.

“I am not suggesting that we should kill all wild pigs. But we should consider tougher actions to control the population of wild pigs and prevent them from colonising the residential areas.”

The district councillor also expressed concern that the wild hogs roaming the hillsides could loosen soil and could cause a landslide in heavy rain.

“In some overseas countries, they can hunt or kill wild pigs,” Chan said. “But in Hong Kong, we have been very kind to them. We catch the boars and then we would release them back to the countryside after giving them contraceptive injections. It won’t reduce their population and after some time they will return to the urban areas for food.”

A member of the department’s advisory committee on agriculture and fisheries, Dr Yau Wing-kwong, agreed “some way to control the population” was needed, but said “some kind people” kept feeding the wild pigs which attracted them to the urban areas.

Fellow district councillor Cheng Lai-king, of the Democratic Party, however was more sympathetic to the wild hogs, saying: “They are part of our countryside and they come out to the urban areas only because they want food. They have been forced into urban areas for food because of their shrinking habitat.

“Often, people do not dispose of kitchen waste properly and that can also attract the animal to scour rubbish bins for food.”

Wild pigs are not a protected species under Hong Kong law, but anyone hunting them without a permit can be liable to a maximum fine of HK$50,000 upon conviction.

There are two government-recognised wild pig hunting teams, formed by about 30 civilian volunteers. When there are confirmed public reports of damage caused by wild pigs, or they are threatening human safety and property on a frequent basis, the department will notify the hunting teams to conduct hunting operations.

In 2013, teams were deployed 94 times and 55 wild pigs were caught, while the numbers fell to 61 and 45 in 2016.

However, hunting has been suspended since last year pending a department review of the strategies to control nuisance caused by wild pigs.

In the meantime, the department said it would send officers to search for wild pigs and use a tranquilliser dart gun to first get hold of the pigs, then inject them with a contraceptive vaccine, before releasing them back to the wild.

“Removing food sources of wild pigs is the most effective measure to reduce their occurrence at the residential areas or public facilities,” a department spokesman said. “The public is therefore advised not to feed wild pigs.”